Written by Ada’s Medical Knowledge Team
What is gout?
Gout is a type of arthritis caused by an excess of a chemical called uric acid, also called urate. This excess acid in the bloodstream can prompt urate crystals to form around certain joints in the body, most often the big toe, resulting in inflammation.
Uric acid is increased in the body by eating certain high-purine foods, as well as by drinking alcohol. Treatment usually involves avoiding foods that can cause gout, as well as medications to relieve pain and decrease the amount of uric acid in the body. Many people are able to manage and avoid episodes of gout using these measures.
Typical symptoms are severe pain in one or more joints, accompanied by redness, swelling and difficulty moving the joint. It is a painful condition, but one that usually passes within three to 10 days. 1 However if left untreated, episodes of gout can return over time, increase in severity and lead to complications. If you are concerned you may have gout, try using the Ada app to begin your personal health assessment.
Symptoms of gout
- Severe pain in a joint, most often the big toe
- Joint feels warm to touch
- Difficulty moving the joint
- Other joints in the foot
Because urate crystals do not form as easily in warm areas, such as sites close to the centre of the body, it is unusual for gout to target more central parts of the body such as the hips, shoulders or spine.
This sensitivity to temperature leads to gout symptoms often occurring at night, when the body temperature generally lowers. Additionally, the fluid that has built up in the affected joint during the day will drain away while lying down, resulting in a more concentrated level of uric acid. 6
- An increased heart rate
If you are worried that you may have gout, you can start your free symptom assessment with the Ada app.
Causes of gout
Gout is a very common condition affecting roughly one in every 100 adults. Gout tends to affect more men than women and becomes more common with age. 1
Gout is caused by excess uric acid in the bloodstream, a condition also known as hyperuricemia. 4 This excess uric acid can result in urate crystals forming in and around the joints, causing the joint to become inflamed, painful and red. Gout usually occurs in one joint at a time, most often the big toe.
Uric acid is produced naturally in the body as a by-product of breaking down purines, a type of chemical compound found in certain foods. 8 Usually, the body passes out excess uric acid in the urine. However, if the kidneys cannot expel enough uric acid, it can build up and cause high levels of uric acid in the bloodstream, a state known as hyperuricemia. 1 Although gout is a possible outcome of hyperuricemia, it is important to note that not all people with hyperuricemia will develop gout. 2
Gout is a complex disease and there are often a number of risk factors that contribute towards its development.
Most people who suffer from gout have kidneys that cannot eliminate the required amount of uric acid. The inability to expel enough uric acid from the kidneys is typically a genetic trait. Therefore, gout often runs in families and around one in five cases occur in people with a family history of gout. 1
Purine-rich food and drink can increase uric acid levels in the blood and are a risk factor for gout, especially in people who already have problems with uric acid excretion. Such foods include: 1 2 4
- Red meat
- Organ meat e.g. liver, kidney, heart, or sweetbreads
- Seafoods such as trout, tuna, herring, anchovies, sardines, scallops, or mussels
- High-fructose food and drink such as candy, soda, canned fruit, sweetened yogurt, salad dressing
- Yeast extracts
Alcohol, especially beer, is also high in purines. The risk of gout directly increases with alcohol consumption. 4
Good to know: A high-purine diet is typically more likely to trigger a gout attack in people who are predisposed, either genetically or medically, to problems expelling the necessary levels of uric acid from the body. Consuming purine-rich food and drink can be a contributing factor, but is rarely a sole cause, of gout. 5 Always discuss dietary changes with a doctor.
There is a direct relationship between obesity and the risk of developing gout. This is because overweight bodies tend to produce more insulin, and insulin can inhibit the kidneys’ ability to expel uric acid. 9
Certain medications may raise the levels of uric acid in the body. These include diuretics, also known as water pills, which work by decreasing the amount of fluid in your body and are often used to treat conditions such as high blood pressure. 10 Aspirin and some chemotherapy medicines have also been shown to raise the body’s uric acid levels. ref1
Other medical conditions
- Kidney disease or damage
- High blood pressure, also known as hypertension
- Underactive thyroid gland, also known as hypothyroidism
- Congestive heart failure
- Certain cancers and blood disorders including leukaemia, lymphoma and hemolytic anemia
- Taking a sample of fluid from a swollen joint to be tested for urate crystals
- Blood tests to monitor the amount of uric acid in the blood
- Ultrasounds or X-rays of the joint to look for signs of damage as a result of gout
Treatment of gout
Gout can often be successfully managed through medication and lifestyle changes. There are two main aims to treating gout: 5
- Treating the symptoms of the current gout attack
- Ongoing treatment to reduce the likelihood of gout returning (see Prevention of gout below)
- Non-steroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen or naproxen to help reduce swelling and pain in the joint. These are most effective when taken soon after symptoms begin
- Colchicine, an anti-inflammatory drug. Colchicine is most effective when taken within the first 24 hours of the attack beginning
- Corticosteroids such as prednisone also help to reduce inflammation and are often prescribed to people at risk of side-effects from other medications
- Elevate the inflamed area to above the heart to help reduce swelling. The simplest way to do this is to lie down on a bed or sofa and raise the affected joint on a couple of cushions
- Rest, and avoid vigorous movement as much as possible
- Place ice against the inflamed joint for 20 minutes at a time to help reduce some of the swelling, heat and pain. Always wrap the ice in a clean towel first to avoid direct contact with the skin
- During night time, placing a cage or cradle around the affected joint to reduce the weight of bed sheets may provide some pain relief
Symptoms from a gout attack usually get better within three to 10 days. However, roughly two in every three people who experience an acute attack of gout will have another one within a year. 1 Therefore, preventative measures are often recommended to minimise the likelihood of gout returning.
There are many lifestyle changes that people who are vulnerable to gout can make to reduce the risk of developing the condition. Such changes may also be recommended by a doctor to people who have experienced gout before. Steps that can be taken to reduce the risk of developing gout include: 1 2 3 4
- Maintaining a healthy diet and limiting the intake of purine-rich foods
- Limiting alcohol intake
- Losing weight, if necessary
- Increasing exercise; the Centers for Disease Control and Prevention (CDC) recommends adults undertake 150 minutes of moderate physical activity every week e.g. brisk walking, swimming or cycling
- Keeping hydrated by drinking plenty of water. Adults should aim to drink between one and two liters of water every day. Avoid sodas and fruit juices, which can be high in purines and fructose
- If already taking medication, consult with a doctor to determine if it can increase the risk of gout
- Allopurinol, which reduces the amount of uric acid in the blood. It is often prescribed to people who have already had multiple attacks of gout and can take a couple of months to become fully effective
- Febuxostat also reduces the amount of uric acid in the body, however it has a number of side-effects and is mostly suggested to people who cannot take allopurinol
- Uricosuric drugs such as probenecid, which increase the amount of uric acid the kidneys are able to pass out in the urine
Complications of gout
Although gout can be very painful, complications arising from the condition are uncommon. Some people never develop gout again. However, others with this condition experience recurrent flares which, if left untreated, can turn into chronic gout. Chronic gout can lead to various complications including: 2 13 14 15
- The development of hard bumps under the skin, known as tophi. Tophi are deposits of urate crystals that build up over time in soft tissues, most often in the feet, hands, ankles, wrists and ears. At this stage of gout the condition is often referred to as chronic tophaceous gout. Over time tophi can damage the tissues around the joints, which can cause arthritis and other permanent joint problems
- Kidney stones. Approximately 20 percent of people with gout also develop kidney stones due to urate crystals forming in the kidneys, which in turn can lead to kidney damage
- Joint deformity due to progressive damage of the tissues around the joint
- A chronic disorder known as osteoarthritis, resulting in persistent pain and stiffness to the joints
Early diagnosis and intervention allows most people with gout to make a full recovery. Even people affected by chronic gout can receive treatment to lower the levels of uric acid in the body and resolve certain complications such as tophi and impaired joint function. 16
Q: Why does gout occur most often in the foot?
A: There are a number of factors that contribute to gout often developing in the foot, in particular the big toe. Firstly, gout is a condition that affects the joints in the body and the foot is home to multiple joints. Secondly, the urate crystals which cause gout form more readily in cool temperatures and the feet are significantly cooler than more central joints in the body such as the hips, shoulders or spine. Thirdly, gout is more likely to target an area that has previously been injured or stressed, making the foot especially susceptible. 17
Q: How long does gout last for?
A: An attack of gout usually lasts between three to 10 days. However, anyone who has experienced gout is at a higher risk of developing it again. If left untreated, gout can become a long-term or chronic condition with attacks happening more frequently and with higher intensity. Leaving gout untreated can also lead to further complications such as kidney stones, joint deformity, osteoarthritis and hard bumps forming under the skin known as tophi. Therefore if gout is suspected, a visit to the doctor is always recommended.
Q: What is the difference between primary and secondary gout?
A: Primary gout is the most common category of gout and is usually related to the combination of naturally-occurring risk factors such as genetics and diet. Secondary gout is when a specific cause for the condition can be identified, such as the existence of a medical condition, or taking medications which increase the levels of uric acid in the bloodstream. 5
Q: Are gout and pseudogout the same?
A: No. Although gout and pseudogout have some similar symptoms and treatments, they have entirely different causes and should be treated separately. Gout is caused by excess uric acid in the body, while pseudogout is caused by excess calcium pyrophosphate. This means the preventative measures that can be taken to reduce the risk of developing gout, such as a low-purine diet, are not applicable to pseudogout. 18
Q: Is there a link between diet and gout?
A: Yes. Gout is caused by high levels of uric acid in the bloodstream. Uric acid is produced in the body when breaking down a chemical called purine, which is found in certain foods. 19 Examples of high purine foods are:
- Alcohol, especially beer
- Some fish, seafood and shellfish
- Some meats including organ meat and red meat
A doctor may recommend changes to your diet to reduce the risk of gout attacks returning. However, while diet is a risk factor for gout, it is not the sole cause. A low-purine diet should not be considered a cure for gout and dietary alterations should always be discussed with a doctor.